1. Technical Field
The present invention relates to computer system maintenance. More specifically, it relates to a method for maintaining the vital product data (VPD) of different field replaceable units (FRUs) of a computer system.
2. Background Information
A computer system is composed of many FRUs, namely, circuit boards or parts that can be easily removed from the computer system and replaced, even by someone lacking in-depth product knowledge of the computer system. These FRUs include power supply units, motherboards, socketed microprocessors, primary storage modules (e.g. Radom Access Memories, or RAMs), secondary storage devices (e.g. hard drives and optical drives), video cards, sound cards, and peripherals such as keyboards, mice and printers. Replacing an FRU while the machine is running is known as hot swapping.
Many FRUs have VPD stored thereon. The VPD is a collection of configuration and informational data associated with a particular set of hardware (e.g. an FRU), to allow for the set of hardware to be administered at a system or network level. VPDs may include product model numbers, unique serial numbers, product release levels, maintenance levels, and other information specific to the hardware, as well as user-defined information, such as the building and department location of the hardware. The VPDs are used by a computer system to determine the nature of a specific hardware, and to shield the operation of the computer system from minor changes and variations of hardware implementations.
Since VPDs are of a critical importance to the reliability and extendibility of the computer system, in many computer systems such as the POWER series and zSeries servers of IBM, a primary EEPROM (Electrically Erasable Programmable Read-Only Memory) is utilized to store the VPD for an FRU, whereas a redundant EEPROM is used on the FRU to keep an extra copy of the VPD, in case the primary EEPROM may fail. However, this extra copy brings additional expenses, not only for the additional hardware part (i.e. the redundant EEPROM), but also for additional interface paths that must be wired to the additional hardware part. Other computer systems keep a persistent copy of the VPDs centrally located, e.g. on a service processor. However, this requires a copy of all of the system VPDs to be centrally stored, thereby incurring additional expenses.